In this specification where a document, act or item of knowledge is referred to or discussed, this reference is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of the common general knowledge; or known to be relevant to an attempt to solve any problem with which this specification is concerned.
A winder assembly refers to blind component (or fitting) that is rotatable to, for example, extend and retract a window covering such as a window blind. Such fittings typically have a drive member that is rotatable about a spindle, and engages a cord (for example, a beaded cord or chain). Operation of the cord, by a user, causes the drive member to rotate about the spindle, and a drive mechanism causes that rotation to be transmitted to a blind cylinder.
To extend the blind, the cord is generally pulled in one direction, which rotates the fitting and extends the blind. However, retraction of the blind may sometimes be accomplished using a different mechanism—for example, retraction of the blind may be spring boosted, such that tugging on the blind or on the cord in a blind extending direction releases the blind and causes it to automatically retract. Such systems therefore only require the cord to be pulled in one direction (a blind extending direction).
Dual blind systems have been developed which use two blinds (a front blind and a back blind) to cover a single window. For example, one blind may be made of sheer or partially transparent fabric, which allows natural light to pass through, and the other blind may be a block-out blind which effectively blocks out light passing through the window and affords privacy.
Generally, a dual blind system will use two winders—one for each blind. However, the system may only require a single cord to operate both winders—pulling the cord in one direction operates one winder to extend the associated blind, and pulling the cord in the opposite direction operates the other winder to extend the other blind. The winder of the present invention is particularly suitable for such a system.